I.
1. go
2. visit
3. play
4. works
5. tells
6. helps
7. swim
8. dances
9. takes care
10. leaves
II.
1. is listening
2. is raining
3. is working, isn't working
4. is running, is wanting
5. is speaking, is coming
6. is coming
7. is holding
8. are smelling
9. is snowing
10. is swimming
*Cấu trúc thì hiện tại đơn:
(+) S + V_inf/ V-e,es
(- ) S + don't/ doesn't + V_inf
(? ) Do/ Does + S + V_inf?
*Thì hiện tại tiếp diễn:
(+) S + is/ am/ are + V_ing
(- ) S + is/ am/ are + not + V_ing
(? ) Is/ Am/ Are + S + V_ing?
